Dynamite

"Marty plugged his ears. / Doc twisted the detonator. / The dynamite roared like the loudest, closest clap of thunder Marty had ever heard. He almost stumbled as the ground shook beneath his sneakers. A wall of dirt and bits of rock and brush rained down on top of them. / Marty threw an arm across his face. Doc had calculated that they would be safe here, a hundred yards from the blast. Safe, maybe. Clean, never."